Among the existing technologies, batteries as backup power sources have been used extensively in many areas such as communications, electrical power systems, military equipment, and electric vehicles. As environmental friendly energy sources gradually gained attention and support from people, batteries are being used in more and more systems as the main power supplies. Among these systems, lithium-ion batteries already became the mainstream power sources for the new energy vehicles. The battery's working condition, whether good or poor, directly affects the operational reliability of the entire system.
If the lithium battery is short-circuited, it can lead to situations such as fluid leakage, spontaneous combustion, and even explosion, endangering the battery itself, the electric vehicle, and even personal safety.
The purpose of a battery short-circuit device is to automatically disconnect the battery circuit within the shortest time period when detecting a battery short-circuit condition through a short-circuit protection circuit, thus protecting the battery. The most common battery short-circuit protection method is to compare the sampling current value with the software reference. When the sampling current value is higher than the short-circuit protection reference, the software controls the discharging MOS switch to be disconnected in order to achieve short-circuit protection. The weakness of the above method is that the response time is relatively slow, and the sustained high current through the MOS can easily cause damage to the MOS. In addition, once the software becomes ineffective, the entire system will collapse.